RCW 11.118.080

In construing the language of a trust for an animal, the governing instrument shall be liberally construed to provide the protections of this chapter. It is presumed that language contained in a trust for an animal is not merely precatory or honorary in nature unless it can be shown by clear and cogent evidence that such was the trustor's intent. Extrinsic evidence is admissible in determining the trustor's intent.